| 摘要 |
<p>PURPOSE:To shorten the length of each of pressure chambers, by providing connecting means that keeps a certain distance between first and second pistons when they are not in operation and allows said distance to be shortened when they are actuated, and providing a return spring around the first spring. CONSTITUTION:One end surface of the secondary piston 37 is formed with a bottomed hole 38. A shaft body 45 is threaded into an end of the primary piston 23, and the other end of the shaft 45, that is, a head section 48, is loosely fitted in a bore 50 of a secondary cup holder 42 and the bottomed hole 38. A spring 52 is housed in the bottomed hole 38, and the shaft body 45 is biased to the right by the spring 52. Thus, when the pistons 23, 37 are not in operation, the distance between the pistons 23, 37 is kept constant, while when they are actuated, the spring 52 is compressed and the distance is shortened. Further, between the primary piston 35 and the secondary cup holder 30 secured to the cylinder main body 1, a return spring 33 is provided along the circumference of the piston 33.</p> |
